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tricks for handlebar vibration

jimwjarmour

jimmy armour
Hi guys hope all are well, just replaced the bars on my 1977 r100s/rt for slightly lower and further forward seem comfy, so was wondering what can bee done to reduce handle bar vibs, ? the old rt bars would vibrate also wheel ballance etc fine, was told to fill bar with silicone and let it solidify! to deaden the vibs what do you guys think,bye for now keep safe Jimmy:scratch
 
Is it a high frequency buzz or something more like a road induced vibration? Is it only at one RPM or the whole time? That's a bit unusual to have the bars vibrate on a /7. I would be sure that the mounts are solid. There was a discussion on a K100 where the bar snake was suggested.
 
When I swapped the tall stock RT bars on my R80 to lower bars (K75C bars), I picked up a lot of vibration. I assumed it was the bars, so I bought some R90S bars. Same issue. Swapping back to stock bars fixed the issue. Then for some reason, I decided to re-install the R90S bars and swap to shorter throttle cables. The vibration went away. Apparently the long cables looping around caused the carbs to be out of balance. I dunno why, the long cables worked smoothy and they seemed to return to idle properly. If you new bars are low enough for the short cables, it may be worth a try.
 
thanks everyone

well felt I should answer before this falls off the page just fitted the new bars EMCO aftermarket they are just what I wanted, I have now cut the ends off 1.5 inches on both sides to make them the same length as the BMW RT bars also slipped a lenght of rubber tube inside the bar and reinstalled my aftermarket bar end weights, so all seems good now thank you to those who tried to help, I always knew what I was going to do but wondered if there was any new tricks worth trying ,guess not again keep well and safe Jimmy :wave
 

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Does this vibration just happen at speeds you usually cruise at? Theoretically you can shift natural frequencies by adding mass and/or stiffness or you can reduce them with added damping. Mass and stiffness are about the only things available to most situations, and they only have a square root effect. Damping is something that rarely can be accomplished by us mere mortals and especially to a level that solves a problem.

Silicon plugs inside a handlebar will only add mass and virtually no damping to a resonance.

BTDT many times. Go after the source - if that's possible.

A structural engineer - retired
 
Trick #1: tune up. Carb synch.

BMW twins don't vibrate. When they were expanded to 1000s, they began to provide massage.
 
As said above...airhead vibrates, first check the valve clearances, then cable free play, then warm up ride, then balance the carbs..that solves most vibration issues...even in the handlebars

If it's an R100 and you REALLY want a smooth machine; next time you do a top end job take the time to balance the rods, pistons, and wrist pins side to side. I've had as much as 8grm difference when the engine swallowed a valve and ruined the side..and the owner replaced the piston/cylinder with an Ebay special to get it back on the road...could make a milkshake while riding. Finally got it balanced and smooth as glass..like a different engine.
 
In the old days we used to fill the handlebars with lead bird-shot to help dampen handlebar buzz.
OM
 
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